Sealing sleeve

ABSTRACT

A rotary pump comprising a housing having upper and lower portions removably connected to one another, each of which includes cooperatively arranged walls extending from the bases thereof to form an inner chamber. A piston also having an annular wall is arranged to move in an eccentric fashion such that the annular wall of the piston moves between the outer sidewall of the housing and the inner annular cooperatively positioned walls on the interior of the housing. Drive means comprising a drive shaft is interconnected to the piston by means of a drive shaft extension means mounted on the drive shaft so as to produce an eccentric motion of the piston upon rotation of the shaft. A sealing diaphram is mounted relative to both the housing and the piston so as to completely separate the drive means from any fluid passing through the pump housing.

United States Patent [191 Braun [4 1 Jan. 1,1974

[ SEALING SLEEVE [22] Filed: Mar. 5, 1971 [21] Appl. No.: 121,286

[52] US. Cl 418/56, 418/59, 418/104 1/01, ke Deities 192 [58] Field of Search 418/56, 59, 64,104,142, 6

[56] References Cited UNITED STATES PATENTS 2,028,407 1/1936 Moineau 418/48 2,463,341 3/1949 Wade 418/48 2,290,137 7/1942 Aldridge 418/48 3,463,091 8/1969 Delsuc 418/59 3,473,728 10/1969 Vulliez 418/59 3,560,119 2/1971 Busch et a1. 418/59 3.323,466 6/1967 Ford 418/50 2,133,358 10/1938 McCormack 418/142 3,161,141 12/1964 Refson 418/56 2,353,373 7/1944 Thompson 418/49 FOREIGN PATENTS OR APPLlCATlONS 620,903 3/1949 Great Britain 418/51 1,361,933 4/1964 France 418/50 Primary ExaminerCarlton R. Croyle Assistant Examiner-John J. Vralblik Attorney-Fred S. Lockwood, John D. Dewey, Lloyd L. Zickert, John L. Alex, Joseph P. OHalloran and Eugene M. Cummings [5 7 ABSTRACT A rotary pump comprising a housing having upper and lower portions removably connected to one another, each of which includes cooperatively arranged walls extending from the bases thereof to form an inner chamber. A piston also having an annular wall is arranged to move in an eccentric fashion such that the annular wall of the piston moves between the outer sidewall of the housing and the inner annular cooperatively positioned walls on the interior of the housing. Drive means comprising a drive shaft is interconnected to the piston by means of a drive shaft extension means mounted on the drive shaft so as to produce an eccentric motion of the piston upon rotation of the shaft. A sealing diaphram is mounted relative to both the housing and the piston so as to completely separate the drive means from any fluid passing through the pump housing.

8 Claims, 8 Drawing Figures T PATENTEDJRN 1 9M sum 2 M2 .INVEN TOR.

- T ARTHUR BRAUN V BY I T ATTORNEY.

SEALING SLEEVE BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a rotary pump comprising a piston which is designed to move in eccentric fashion within the pump housing and which includes a sealing means mounted relative to the piston and housing in such a manner as to completely seal off the drive means from any fluid passing through the pump.

2. Description of the Prior Art Numerous pumps utilizing various principles and structures are currently available. However, in view of the great diversity of applications for pumps, there is a need for an efficient, economical and dependable pump structure. It is obvious that the most efficient structure for a pump is dependent upon the individual application for which the pump is desired. There are, however, certain criteria that'may be generally applied to all pumps.

More specifically, a pump must be both economical and efficient. This requires thatthe design, fabrication and materials used in constructing the pump must be carefully selected with both cost and durability being of primary consideration. Ideally, a pump structure should include the minimum number of parts needed to accomplish its intended function thereby allowing for easy and quick assembly while at the same time increasing the durability of the pump structure. With regard to efficiency and operation, a major problem present in a number of the conventional pump structures is concerned with friction. To overcome the friction problem both the number and arrangement of moving parts which comprise the pump structure must be carefully considered so that forces exerted across any moving surfaces be held to a minimum.

With respect to the performance and operation, it is also important that the pump be designed to provide an adequate flow rate. This should be accomplished at a reasonable operating speed for a sufficiently large volume per cycle while at all times maintaining a smooth operation.

Conventional pumps, in anattempt to overcome the above problems, have been designed to include relatively complex structures which involve a number of moving parts and thereby may be generally considered expensive and unreliable for various applications. The versatility of many of the known pump structures is also limited because of the type of fluid intended to be directed through the pump. The use of a plurality of moving parts in many pump structures prohibits these structures from pumping corrosive fluids. which have the tendency to wear away any such moving parts exposed to the interior of the pump housing. Attempts to overcome this problem have also resulted in the provision of complicated, and therefore expensive, sealing means which are intended to separate a number of exposed working parts from any fluid passing through the pump housing.

SUMMARY OF THE INVENTION The present invention relates to a rotary, wobbletype pump having a simple, low-cost, and reliable structure which overcomes the problems prevalent in conventional pump structures.

More specifically, the pump comprises a driven piston mounted to be movable, in an eccentric fashion,

within piston mounted to be movable, in an eccentric fashion, within a pump housing. The housing is made from an upper and lower portion removably attached to each other and one or both including an annular wall extending from the respective bases thereof. The walls are cooperatively arranged relative to one another to define an inner chamber arranged in communicating relation with an inlet to the pump housing. The piston also includes an annularly shaped drive wall mounted on the piston so as to be positioned between the outer side wall of the housing and the cooperatively positioned annular walls extending from the upper and lower portions of the pump housing.

The pump further includes a drive comprising a rotationally mounted driveshaft which is interconnected to the piston by means of a drive shaft extension means fixedly mounted on the drive shaft in such a manner as to cause eccentric motion of the piston upon rotation of the drive shaft. This eccentric motion may be caused by arranging the extension means in various positions relative to the longitudinal axis of the drive shaft. More specifically, one embodiment of the present invention comprises the extension means arranged in an angular relation to the longitudinal axis of the drive shaft. A hollow sleeve is mounted over the extension means such that rotation of the drive shaft causes relative movement between the rotation of the drive shaft mounted thereon. This produces a substantially universal action which in turn provides eccentric motion to the piston. Altemately the extension may be arranged in parallel relationship to the longitudinal axis of the drive shaft. Bearing means are provided to interconnect the extension means and the piston whereupon rotation of the drive shaft causes the eccentric motion of the piston.

In yet another embodiment of the invention, the extension means comprises an eccentric fixedly mounted on the drive shaft intermediate its extremities and connected to the piston by hearing means such that rota tion of the eccentric along with the drive shaft causes an eccentric motion of the piston within the pump housing.

The pump structure further includes a sealing means in the form of at least one diaphragm made from flexible material and having an annular configuration. The sealing means is arranged within the pump housing in relation to both the housing interior and the piston such that at least a portion of the drive means is separated in sealed fashion from any fluid passing through the pump.'Alternately, depending upon the location of the drive means, the sealing means may be located outside the pump housing. Regardless of its location, the sealing means is provided to allow various fluids including corrosive liquids to be directed through the pump without deteriorating any exposed parts of the drive means.

In operation, liquid passes into the inner chamber defined by the annular walls extending from the respective basis of the upper and lower portion of the pump housing. In that the extension means is fixedly wcured to the drive shaft, rotation of the drive shaft causes the piston to rotate in an eccentric manner about the longitudinal axis of the drive shaft. Fluid within the inner chamber flows through an exhaust slot formed in at least one of the annular extending walls and is directed around the outside of said wall by the action of the piston until it reaches another exhaust slot communicating with an outlet port in the housing. As the fluid passes through the pump housing, it is separated, in sealed fashion, from the drive shaft, drive shaft extension means and bearing means by which the piston is connected to the extension means.

It should be further noted that if desired, an array of pumps, each utilizing the basic structure just described, may be used, and the only change necessary would be the relocation or repositioning of the inlet and outlet port and additional use of a shaft connecting means. The pump in the present invention may also be used as a hydraulic motor by simply injecting fluid through the inlet or the outlet and using the shaft as the driven member.

From the above description it is evident that the parts comprising the pump structure can be easily and cheaply mass-produced. The simple design of the parts also aid in efflcient, economic assembly of the pump structure. An additional advantage is that, in use the pump has an extremely small size for the volume of fluid it is capable of pumping. Because of both the material used in construction and the provision of the sealing means, it may be used to pump gases, liquids and even suspensions whether such fluids are corrosive or non-corrosive.

The invention accordingly comprises the features of construction, combination of elements, and arrangement of parts which will be exemplified, in the construction hereinafter set forth and the scope of the invention will be indicated in the claims.

BRIEF DESCRIPTION OF THE DRAWINGS For a fuller understanding of the nature and objects of the invention, reference should be had to the following detailed description taken in connection with the accompanying drawings in which:

FIG. 1 is a front perspective view of the assembled pump structure of the present invention.

FIG. 2 is a side sectional view taken along line 2-2 of FIG. 1 showing the interior of the pump housing.

FIG. 3 is a top sectional view taken along lines 33 of FIG. 2 showing the interior of the pump housing.

FIG. 4 is a top sectional view taken along lines 4 4 of FIG. 2 showing one embodiment of the sealing means.

FIG. 5 is a side sectional view of the interior of the pump housing showing a second embodiment of the drive shaft extension.

FIG. 6 is a side cross-sectional view of the interior of the pump housing showing another embodiment of the drive shaft extension.

FIG. 7 is a side cross-sectional view showing the interior of the pump housing and disclosing yet another embodiment of the drive shaft extension.

FIG. 8 is a side cross-sectional view showing the interior of the pump housing and disclosing yet another embodiment of the drive shaft extension.

Similar reference characters refer to similar parts throughout the several views of the drawings.

DETAILED DESCRIPTION The pump of the present invention comprises a pump housing generally indicated at 10 in FIG. 1 and has an upper portion 12 and a lower portion 14. These portions may be removably connected to one another by means of a snap fit arrangement comprising a peripheral lip 16 designated to engage the peripheral groove 18 formed on the interior surface of upstanding flange 20 of the lower portion 14. Other applicable means could be used for connecting the portions of housing 10 together in either a fixed or separable manner, depending upon the specific application of the pump. The housing 10 further includes inlet and outlet ports 21 and 23 respectively which may be arranged on the upper portion 12 as shown in FIG. 2.

Referring to FIGS. 2 and 3, the interior of housing 10 comprises an inner chamber 22 partially defined by interior annular walls 24 and 26 extending from the bases 28 and 30 of the upper and lower portions of the housing 10 respectively. An outer chamber 34 is defined between side wall 32 of the housing 10 and the annular walls 24 and 26 of the upper and lower portions respectively. This outer chamber 34 communicates directly with outlet port 23 as shown.

A piston 36 is mounted to move within outer chamber 34 of housing 10 in an eccentric fashion by rotation of drive means generally indicated at 38 and which will be described hereinafter. The piston comprises an annular drive wall 40 centrally mounted on disc 42 and having a diameter such that wall 40 is positioned between outer wall 32 and inner annular walls 24 and 26. Drive wall 40 is also positioned such that the volumes on the inside and outside of wall 40 be substantially equal to prevent force leakage of incompressible fluids. Piston wall 40 contains an inner piston exhaust slot 44 which straddles separator wall 46 interconnecting inner wall 24 and outer wall 32. Similarly, the inner chamber 22 communicates with the area on the inside of drive wall 40 by means of a second exhaust slot 47. Through the pumping action of piston drive wall 40, which will be explained hereinafter, the fluid passing through the pump eventually is forced out of outlet port 23 by passing through a third exhaust slot 48 arranged at the interior extremity of outlet port 23.

The drive means used to provide eccentric motion to the piston 36 comprises a drive shaft 50 which may be rotationally mounted on the exterior of the housing 10. As shown in FIGS. 2, 5 and 6, a drive shaft extension means 52 is mounted on the upper end of the drive shaft and is positioned to extend into chamber 22 of housing 10 in such a manner as to interconnect piston 36 and the drive shaft 50.

An important features of the present invention is the provision of a sealing means which comprises a diaphram 54 arranged on the interior of housing 10 so as to separate, in a sealing fashion, at least a portion of the drive means from any fluid passing through the pump housing. This sealing means therefore greatly extends the operable life of the pump since no corrosive or noncorrosive fluids can reach the working portions of the drive means including the drive shaft.

In the embodiment of FIG. 2, an elongated sleeve 56 is movably mounted on drive shaft extension 52 which itself is angularly arranged on drive shaft 50 relative to the longitudinal axis thereof. Bearing means may be provided between extension 52 and sleeve 56 so as to facilitate relative movement therebetween. A flexible connection means in the form of a flexible member 57, extends between the upper portion of sleeve. 56 and disc 42 of the piston. An eccentric or wobble-like mo tion is thereby provided to piston 36 in that, upon rotation of drive shaft 50, sleeve 56 moves in a universal fashion due to its ability of moving relative to extension 52 and the angular arrangement of extension 52 relative to drive shaft 50. FIG. 4 shows the sealing means of FIG. 2 which includes a flexible diaphram 54 connected to both the lower extremity of the sleeve 56 and the housing as to seal off at least drive shaft 50 from the interior of the pump housing 10.

In the embodiments shown in FIGS. 5 and 6, the extension 52 is mounted on the upper extremity of drive shaft 50 in parallel, non-colinear relationship to the longitudinal axis of shaft 50. The piston 36 is movably attached to the upper extremity of extension 52 by hearing means 58 arranged on the interior of hub 60 formed in the center of disc 42. As shown in FIG. 5 extension 52 may be integrally formed on the upper extremity of shaft 50 and the sealing means comprises a flexible diaphram extending from the lower extremity of hub 60 to an upper peripheral lip partially defining the entrance of extension 52 into housing 10. The embodiment of FIG. 6, on the other hand, shows extension 52 being movably attached to the upper extremity of shaft 50. The sealing means comprises a flexible diaphram having its upper portion attached to the lower extremity of hub 60 and having its lower extremity connected to the interior wall surface of chamber 22.

The embodiment shown in FIG. 7 differs somewhat from the above discussed embodiment of FIGS. 2, 5 and 6 in that drive shaft 50 extends within the interior of housing and is movably mounted therein by bearing means 62 and 64. In this embodiment, the extension means comprises an eccentric 66 fixedly attached to shaft 50 and movably connected to disc 42 by additional bearing means 68. In this embodiment the sealing means comprises first and second flexible diaphrams 70 and 72 each having one end connected to the central hub 60 of disc 46 and the opposite ends connected to the housing such that the entire drive means and eccentric 66 are separated from any fluid being directed through the pump housing 10.

The embodiment shown in FIG. 8 is somewhat similar to that of the embodiment of FIG. 2 in that the extension 52 is arranged at an annular relation to drive shaft 50. However, as shown in FIG. 8 the extension 52 is movably attached to the upper extremity of shaft 50 by means of shaft extension 74 being mounted in bearings 76 as shown. As shaft 50 rotates, extension 52 remains fixed relative to sleeve 56 and moves relative to shaft 50 due to bearing 76. Accordingly, similar universal action is supplied to sleeve 56 which in turn drives through connecting means 57.

In operation, piston 36 wobbles or moves in an eccentric manner within housing 10 as drive shaft 50 rotates. Considering a clockwise rotation, as piston 36 moves through its cycle, two lines of contact occur between wall 40 of the piston and walls 24, 26 and 32 of the housing. These lines will progress in a counterclockwise fashion as the piston 36 is wobbled. As this occurs, the volume exposed to inlet port 21 between wall 24, 26 and wall 40 of the piston increases. This draws fluid in through port 21 and subsequently through exhaust slot 46.

After piston 36 has made one 360 cycle, the volume enclosed by piston wall 40 is completely filled with fluid. On the next 360 cycle, the fluid is expelled into the outer volume between piston wall 40 and the outer cylinder wall 32, but on the other side of separator wall 47. New fluid is also drawn into the volume enclosed by wall 40. On the next 360 cycle, the fluid is expelled from between walls 40 and 32, out through outlet 23,

while the fluid within chamber 22 is expelled through exhaust slot 46.

During such motion of the piston, exhaust slot 44 is opened and closed on opposite sides of separator wall 47.

Once started, the pump draws fluid in through inlet 21, forces it from the inside to the outside of wall 40 and then out the outlet 23. The direction of rotation of the piston 36 is obviously of no moment. The pump of this invention may be used with clockwise or counterclockwise rotary motion of the piston and no priming is necessary.

During the above operation, regardless of the embodiment utilized, the sealing means is arranged relative to the housing and to the piston such that at least a portion of the drive means is separated, in a sealed fashion, from any fluid passing through the pump housing. This of course extends the operable life of the pump since no fluid can reach the working parts of the drive means. In addition, the pump has increased versatility since both corrosive and non-corrosive fluids can be directed through the pump housing without fear of undue wear on the drive means.

It will thus be seen that objects made apparent from the preceding description are efficiently attained and since certain changes may be made in the above construction without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

It is also to be understood that the following claims are intended to cover all of the generic and specific fea tures of the invention herein described and all statements of the scope of the invention which, as a matter of language may be said to fall therebetween.

Now that the invention has been described,

What is claimed is:

1. A pump capable of pumping corrosive fluids, said pump comprising: a housing including an inlet port and an outlet port, an inner chamber communicating with said inlet port, a piston movably mounted within said housing, said housing having an outer side wall, said housing also including an axially extending annular wall extending from said housing and defining an inner chamber, said piston including an annularly shaped drive wall mounted on the piston.

2. A pump as in claim 1 wherein said sealing means is fonned from a flexible material.

3. A pump as in claim 1 wherein said extension means is connected to said drive shaft in angular relation to the longitudinal axis thereof, whereby rotation of said drive shaft causes eccentric motion of said piston relative to said axis.

4. A pump as in claim 1 wherein said sealing means comprises at least one flexible diaphragm and said flexible connection means, said diaphragm interconnected between said drive means and said housing, and said flexible connection means interconnected between said drive means and said piston a spaced distance from said diaphragm, whereby at least said drive shaft is sealed from any fluid passing through said housing.

5. A pump as in claim 3 wherein said extension means is fixedly secured to said drive shaft; and said pump comprises a sleeve mounted on said extension means and attached to said piston, whereby rotation of and attached to said piston, whereby rotation of said drive shaft causes universal movement of said sleeve and eccentric motion of said piston.

8. A pump as in claim 7 wherein said flexible connection means is interconnected between said sleeve and said piston, said extension means being fixedly attached to said sleeve, whereby movement of said sleeve causes movement of said piston.

Patent No. ,782,865 Dated January 1, 1974 Invent r( Arthur R. Braun It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

In column l, line 67, and column 2, line I, delete "in an eccentric fashion, within piston mounted to be movable".

In column 3, line 66, "designated" should be --designed--. In column 6, line 24, after "that" insert --the-. In claim 1, line 9, after "piston" the period should be changed to a comma and then insert the following: --said drivewall extending axially and being positioned between the outer side wall and said axially extending annular wall of said housing to define distinct variable volume chambers between said outer side wall and said axially extending annular wall of said housing, one of said distinct variable volume chambers being radially inwardly and the other being radially outwardly with respect to said drive wall; and. a generally radially extending channel-defining wall connecting said outer side wall and said axially extending annular wallof said housing, said channel-defining wall being positioned with the entry of one of said ports on one side of said channel-defining wall, and the entry of the other of said ports being on the other side of said channel-defining wall; drive means arranged to drive said piston and including a drive shaft, extension means mounted on said drive shaft for moving said piston in eccentric motion, and flexible connection means interconnected between said piston and said drive means, and sealing means connected to both said housing and said drive means so as to separate said drive means in sealed relation from liquid passing through said pump, said flexible connection means consisting essentially of a diaphragm of flexible material extending generally transversely of said extension means, said connection means also including means for securing said diap ragm at a mid-portion thereof to said extension means, and means for securing said diaphragm at i an outer periphery thereof to said piston.

Signed and sealed this 29th day of October 1974.

(SEAL) Attest:

McCOY M. GIBSON JR. 0. MARSHALL DANN Attesting Officer Commissioner of Patents FORM PO-IOSO (10-59) 

1. A pump capable of pumping corrosive fluids, said pump comprising: a housing including an inlet port and an outlet port, an inner chamber communicating with said inlet port, a piston movably mounted within said housing, said housing having an outer side wall, said housing also including an axially extending annular wall extending from said housing and defining an inner chamber, said piston including an annularly shaped drive wall mounted on the piston.
 2. A pump as in claim 1 wherein said sealing means is formed from a flexible material.
 3. A pump as in claim 1 wherein said extension means is connected to said drive shaft in angular relation to the longitudinal axis thereof, whereby rotation of said drive shaft causes eccentric motion of said piston relative to said axis.
 4. A pump as in claim 1 wherein said sealing means comprises at least one flexible diaphragm and said flexible connection means, said diaphragm interconnected between said drive means and said housing, and said flexible connection means interconnected between said drive means and said piston a spaced distance from said diaphragm, whereby at least said drive shaft is sealed from any fluid passing through said housing.
 5. A pump as in claim 3 wherein said extension means is fixedly secured to said drive shaft; and said pump comprises a sleeve mounted on said extension means and attached to said piston, whereby rotation of said drive shaft causes universal movement of said sleeve and eccentric motion of said piston.
 6. A pump as in claim 5 wherein said flexible connection means is interconnected between said sleeve and said piston, whereby movement of said sleeve causes movement of said piston.
 7. A pump as in claim 3 wherein said extension is movably attached to said drive shaft; said pump further comprises a sleeve mounted on said extension means and attached to said piston, whereby rotation of said drive shaft causes universal movement of said sleeve and eccentric motion of said piston.
 8. A pump as in claim 7 wherein said flexible connection means is interconnected between said sleeve and said piston, said extension means being fixedly attached to said sleeve, whereby movement of said sleeve causes movement of said piston. 